diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index 87246be6feb8513b4a97e74ada1ca3f2fa72fa9d..97734ced947e1d9f8222ca835287e6ecd876688a 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -37,6 +37,7 @@ hostprogs-y += xdp_tx_iptunnel
hostprogs-y += test_map_in_map
hostprogs-y += per_socket_stats_example
hostprogs-y += load_sock_ops
+hostprogs-y += xdp_redirect
# Libbpf dependencies
LIBBPF := ../../tools/lib/bpf/bpf.o
@@ -78,6 +79,7 @@ lwt_len_hist-objs := bpf_load.o $(LIBBPF) lwt_len_hist_user.o
xdp_tx_iptunnel-objs := bpf_load.o $(LIBBPF) xdp_tx_iptunnel_user.o
test_map_in_map-objs := bpf_load.o $(LIBBPF) test_map_in_map_user.o
per_socket_stats_example-objs := $(LIBBPF) cookie_uid_helper_example.o
+xdp_redirect-objs := bpf_load.o $(LIBBPF) xdp_redirect_user.o
# Tell kbuild to always build the programs
always := $(hostprogs-y)
@@ -119,6 +121,7 @@ always += tcp_bufs_kern.o
always += tcp_cong_kern.o
always += tcp_iw_kern.o
always += tcp_clamp_kern.o
+always += xdp_redirect_kern.o
HOSTCFLAGS += -I$(objtree)/usr/include
HOSTCFLAGS += -I$(srctree)/tools/lib/
@@ -155,6 +158,7 @@ HOSTLOADLIBES_tc_l2_redirect += -l elf
HOSTLOADLIBES_lwt_len_hist += -l elf
HOSTLOADLIBES_xdp_tx_iptunnel += -lelf
HOSTLOADLIBES_test_map_in_map += -lelf
+HOSTLOADLIBES_xdp_redirect += -lelf
# Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline:
# make samples/bpf/ LLC=~/git/llvm/build/bin/llc CLANG=~/git/llvm/build/bin/clang
diff --git a/samples/bpf/xdp_redirect_kern.c b/samples/bpf/xdp_redirect_kern.c
new file mode 100644
index 0000000000000000000000000000000000000000..a34ad457a684aab700f032598375d79707c51051
--- /dev/null
+++ b/samples/bpf/xdp_redirect_kern.c
@@ -0,0 +1,81 @@
+/* Copyright (c) 2016 John Fastabend <john.r.fastabend@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#define KBUILD_MODNAME "foo"
+#include <uapi/linux/bpf.h>
+#include <linux/in.h>
+#include <linux/if_ether.h>
+#include <linux/if_packet.h>
+#include <linux/if_vlan.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include "bpf_helpers.h"
+
+struct bpf_map_def SEC("maps") tx_port = {
+ .type = BPF_MAP_TYPE_ARRAY,
+ .key_size = sizeof(int),
+ .value_size = sizeof(int),
+ .max_entries = 1,
+};
+
+struct bpf_map_def SEC("maps") rxcnt = {
+ .type = BPF_MAP_TYPE_PERCPU_ARRAY,
+ .key_size = sizeof(u32),
+ .value_size = sizeof(long),
+ .max_entries = 1,
+};
+
+
+static void swap_src_dst_mac(void *data)
+{
+ unsigned short *p = data;
+ unsigned short dst[3];
+
+ dst[0] = p[0];
+ dst[1] = p[1];
+ dst[2] = p[2];
+ p[0] = p[3];
+ p[1] = p[4];
+ p[2] = p[5];
+ p[3] = dst[0];
+ p[4] = dst[1];
+ p[5] = dst[2];
+}
+
+SEC("xdp_redirect")
+int xdp_redirect_prog(struct xdp_md *ctx)
+{
+ void *data_end = (void *)(long)ctx->data_end;
+ void *data = (void *)(long)ctx->data;
+ struct ethhdr *eth = data;
+ int rc = XDP_DROP;
+ int *ifindex, port = 0;
+ long *value;
+ u32 key = 0;
+ u64 nh_off;
+
+ nh_off = sizeof(*eth);
+ if (data + nh_off > data_end)
+ return rc;
+
+ ifindex = bpf_map_lookup_elem(&tx_port, &port);
+ if (!ifindex)
+ return rc;
+
+ value = bpf_map_lookup_elem(&rxcnt, &key);
+ if (value)
+ *value += 1;
+
+ swap_src_dst_mac(data);
+ return bpf_redirect(*ifindex, 0);
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/samples/bpf/xdp_redirect_user.c b/samples/bpf/xdp_redirect_user.c
new file mode 100644
index 0000000000000000000000000000000000000000..761a91d5d7b47a80c523a7f228e232722867057a
--- /dev/null
+++ b/samples/bpf/xdp_redirect_user.c
@@ -0,0 +1,102 @@
+/* Copyright (c) 2016 John Fastabend <john.r.fastabend@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#include <linux/bpf.h>
+#include <assert.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "bpf_load.h"
+#include "bpf_util.h"
+#include "libbpf.h"
+
+static int ifindex_in;
+static int ifindex_out;
+
+static void int_exit(int sig)
+{
+ set_link_xdp_fd(ifindex_in, -1, 0);
+ exit(0);
+}
+
+/* simple per-protocol drop counter
+ */
+static void poll_stats(int interval, int ifindex)
+{
+ unsigned int nr_cpus = bpf_num_possible_cpus();
+ __u64 values[nr_cpus], prev[nr_cpus];
+
+ memset(prev, 0, sizeof(prev));
+
+ while (1) {
+ __u64 sum = 0;
+ __u32 key = 0;
+ int i;
+
+ sleep(interval);
+ assert(bpf_map_lookup_elem(map_fd[1], &key, values) == 0);
+ for (i = 0; i < nr_cpus; i++)
+ sum += (values[i] - prev[i]);
+ if (sum)
+ printf("ifindex %i: %10llu pkt/s\n",
+ ifindex, sum / interval);
+ memcpy(prev, values, sizeof(values));
+ }
+}
+
+int main(int ac, char **argv)
+{
+ char filename[256];
+ int ret, key = 0;
+
+ snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+
+ if (ac != 3) {
+ printf("usage: %s IFINDEX_IN IFINDEX_OUT\n", argv[0]);
+ return 1;
+ }
+
+ ifindex_in = strtoul(argv[1], NULL, 0);
+ ifindex_out = strtoul(argv[2], NULL, 0);
+
+ if (load_bpf_file(filename)) {
+ printf("%s", bpf_log_buf);
+ return 1;
+ }
+
+ if (!prog_fd[0]) {
+ printf("load_bpf_file: %s\n", strerror(errno));
+ return 1;
+ }
+
+ signal(SIGINT, int_exit);
+
+ if (set_link_xdp_fd(ifindex_in, prog_fd[0], 0) < 0) {
+ printf("link set xdp fd failed\n");
+ return 1;
+ }
+
+ /* bpf redirect port */
+ ret = bpf_map_update_elem(map_fd[0], &key, &ifindex_out, 0);
+ if (ret) {
+ perror("bpf_update_elem");
+ goto out;
+ }
+
+ poll_stats(2, ifindex_out);
+
+out:
+ return 0;
+}